1. Edit the Login and rename it to NewMailboxName@Postoffice2. Edit the Mailbox and rename the MailboxName3. Find All AddressMaps for the Mailbox and map to the new mailbox4. Access the File System and Rename the MailboxName.Sys File Under the Config/Postoffices/Mailbox directory5. Access the File System and Rename the Postoffices/Postoffice/MailBox to have the new mailbox name - since this will place all the emails into the location of the new mailbox.